Chiapas, a small village that is about 10 kilometres from San Cristobal de las Casas is well known for retaining its Tzotzil Indian traditions.
The local handicrafts are really pretty. On the other hand, the local people are really poor and sometimes willing to sell whatever the price, even if it costs them money...which you should remember when you are bargaining.
Summary:San Juan de Chamula is very special, you either love it or you hate it.
I tended more to the second option, because its hyper touristy side hides the authenticity that everyone tries to sell us when they talk about this town. The really annoying thing is that the town's atmosphere reminds you of places that specialise in mass tourism, even though the place itself isn't that touristy.